US6988514B2 - Hydroaccumulator, in a particular a bladder accumulator - Google Patents

Hydroaccumulator, in a particular a bladder accumulator Download PDF

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Publication number
US6988514B2
US6988514B2 US10/399,445 US39944503A US6988514B2 US 6988514 B2 US6988514 B2 US 6988514B2 US 39944503 A US39944503 A US 39944503A US 6988514 B2 US6988514 B2 US 6988514B2
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United States
Prior art keywords
fluid
valve body
connecting sleeve
hydroaccumulator
fluid channel
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime, expires
Application number
US10/399,445
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English (en)
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US20040020543A1 (en
Inventor
Norbert Weber
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Hydac Technology GmbH
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Hydac Technology GmbH
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Publication date
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Assigned to HYDAC TECHNOLOGY GMBH reassignment HYDAC TECHNOLOGY GMBH ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: WEBER, NORBERT
Publication of US20040020543A1 publication Critical patent/US20040020543A1/en
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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B1/00—Installations or systems with accumulators; Supply reservoir or sump assemblies
    • F15B1/02—Installations or systems with accumulators
    • F15B1/04—Accumulators
    • F15B1/08—Accumulators using a gas cushion; Gas charging devices; Indicators or floats therefor
    • F15B1/22—Liquid port constructions
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B1/00—Installations or systems with accumulators; Supply reservoir or sump assemblies
    • F15B1/02—Installations or systems with accumulators
    • F15B1/04—Accumulators
    • F15B1/08—Accumulators using a gas cushion; Gas charging devices; Indicators or floats therefor
    • F15B1/10—Accumulators using a gas cushion; Gas charging devices; Indicators or floats therefor with flexible separating means
    • F15B1/16—Accumulators using a gas cushion; Gas charging devices; Indicators or floats therefor with flexible separating means in the form of a tube
    • F15B1/165—Accumulators using a gas cushion; Gas charging devices; Indicators or floats therefor with flexible separating means in the form of a tube in the form of a bladder
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2201/00—Accumulators
    • F15B2201/20—Accumulator cushioning means
    • F15B2201/205—Accumulator cushioning means using gas
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2201/00—Accumulators
    • F15B2201/30—Accumulator separating means
    • F15B2201/315—Accumulator separating means having flexible separating means
    • F15B2201/3152—Accumulator separating means having flexible separating means the flexible separating means being bladders
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2201/00—Accumulators
    • F15B2201/40—Constructional details of accumulators not otherwise provided for
    • F15B2201/41—Liquid ports
    • F15B2201/411—Liquid ports having valve means
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2201/00—Accumulators
    • F15B2201/40—Constructional details of accumulators not otherwise provided for
    • F15B2201/43—Anti-extrusion means
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/7722—Line condition change responsive valves
    • Y10T137/7781—With separate connected fluid reactor surface
    • Y10T137/7784—Responsive to change in rate of fluid flow
    • Y10T137/7792—Movable deflector or choke

Definitions

  • the present invention relates to a hydroaccumulator, in particular a bladder accumulator, with a pressure tank and a separating element located in and separating a gas space from a fluid space in the pressure tank.
  • the gas space borders a gas-side access.
  • the fluid space borders a fluid-side access having a fluid connecting sleeve and a valve arrangement located in the connecting sleeve.
  • the valve includes a valve body having at least one transverse hole and is normally pretensioned into its open position to clear the fluid passage, and can be moved into its closed position by the displacement of the separating element.
  • the inside surface of the connecting sleeve for the valve body directly adjoining the valve body forms the guide for its displacement between the open position and the closed position.
  • Hydraulic accumulators with valves operated by the separating element are commercially available.
  • a bladder accumulator of this type is depicted and described.
  • the valve arrangement comprises a seat valve.
  • a conical surface is formed on the end edge of a connecting sleeve facing the fluid space to provide a stationary valve seat. The conical surface interacts with a corresponding conical surface on the valve plate of the movable valve body.
  • valve is made similarly to the control valves conventionally used in valve-controlled internal combustion engines, i.e., the valve plate is located on a shaft guided in a valve guide for the valve lifting motion between the open position and closed position.
  • the valve guide is installed in the connecting sleeve.
  • PCT/WO 00/31420 discloses a generic hydraulic accumulator with a separating element formed from metal bellows. Within the bellows is a compression spring which keeps the separating element in the pretensioned state. On its bottom, the bellows is provided with an end plate which interacts with a valve body accommodated in the fluid connecting sleeve of the housing of the known hydraulic accumulator and held under spring pretension.
  • the valve body is made as a valve lifter and is larger in dimensions in its lengthwise alignment than in the transverse direction. Thus, the known valve body occupies considerable space in its direction of displacement in the connecting sleeve.
  • the end of the valve body interacting with the end plate is made dome-like.
  • the height is several times larger than its diameter.
  • the valve body is formed on its side facing the separating element as a plate.
  • the plate is flat.
  • Its sleeve-like outside jacket has transverse holes diametrically opposite one another and connected to the fluid side of the hydraulic accumulator in the open position of the valve to carry fluid.
  • the known valve body approach accordingly has a very large structure in the axial direction of the hydraulic accumulator. Due to the fluid-carrying transverse holes, the flow behavior cannot be choked and is consequently unfavorable in the area of inflow of the medium into the fluid space.
  • Objects of the present invention are to provide a hydraulic accumulator where the valve body occupies little space, is geometrically simple in structure, can be economically implemented, and allows optimized flow behavior in the area of the flow into the fluid space.
  • the valve arrangement is made in the manner of a plate valve occupying little space and can be economically implemented.
  • the respective fluid channel is integrated into the interior of the valve body allowing controlled triggering of the fluid flow.
  • the fluid channels can be chosen in terms of their number and cross-sectional size. As fluid passes, the desired choking takes place, with the possibility of stipulating the damping conditions which are optimum when the hydraulic accumulator is in operation, depending on the intended application.
  • valve arrangement is a sliding valve
  • the connecting sleeve being used as the valve housing and with its circular cylindrical inside surface defining the piston bore for the valve body which is made as a sliding piston.
  • the end edge of the piston bore of the connecting sleeve which edge borders the fluid space, forms the control edge for clearing and closing one or more fluid channels of the sliding piston.
  • the piston bore which guides the sliding piston can preferably have, on its end area adjacent to the fluid space, a tapered hole section.
  • An annular shoulder surface is then formed, which in interaction with an opposing shoulder surface which projects radially on the sliding piston, forms a stop against which the sliding piston rests in the open position of the valve.
  • FIG. 1 is a partial, side elevational view in section of a bladder accumulator according to a first embodiment of the present invention, with only the part of the accumulator adjacent to the fluid-side connecting sleeve being illustrated and with the valve arrangement illustrated in the open position;
  • FIG. 2 is a side elevational view in section of only the fluid connecting sleeve of a bladder accumulator according to a second embodiment of the present invention, on a much larger scale compared to FIG. 1 , with the valve arrangement illustrated in the closed position; and
  • FIG. 3 is a partial, side elevational view in section of a bladder accumulator according to a third embodiment of the present invention on the left side and according to a fourth embodiment of the present invention on the right side, with the valve arrangement being shown in the open position.
  • FIG. 1 only the section of the pressure tank adjacent to the fluid-side access 3 is shown.
  • the opposite end area (not shown) of the pressure tank 1 has a conventionally configured gas-side access to the interior space of a storage bladder 5 (only schematically illustrated in FIG. 3 ).
  • Storage bladder 5 forms the movable separating element separating the gas space 7 from the fluid space 9 in the interior of the pressure tank.
  • the fluid-side access 3 comprises a fluid connecting sleeve 11 welded onto the end wall of the pressure tank 1 adjacent to the fluid space 9 .
  • the connecting sleeve 11 is a circularly cylindrical sleeve and has an inside thread 13 on its outer free end for the connection of a fluid line (not shown).
  • the connecting sleeve 11 forms a piston bore 15 in which a sliding piston 17 is movably guided.
  • the connecting sleeve 11 thus forms the valve housing for a sliding valve with the sliding piston 17 used as the movable valve body and guided on the inside surface of the piston bore 15 of the connecting sleeve 11 directly for its displacement along the lengthwise axis 19 of the piston bore 15 .
  • Sliding piston 17 can be moved between the open position shown in FIGS. 1 and 3 , and the closed position shown in FIG. 2 .
  • the sliding piston 17 is pretensioned by a helical compression spring 21 into the open position shown in FIGS. 1 and 3 . From this position, the sliding piston can be moved with the corresponding expansion of the storage bladder 5 against the force of the compression spring 21 into the closed position shown in FIG. 2 when the storage bladder presses against the top 23 of the accumulator sliding piston 17 .
  • the compression spring 21 is supported with its end facing away from the sliding piston 17 on a support plate 25 .
  • the support plate adjoins a shoulder located on the adjacent end of the piston bore 15 in the connecting sleeve 11 .
  • support plate 25 is held by a retaining ring 27 .
  • the support plate 25 is secured by a flat snap ring 29 .
  • the embodiment of FIG. 2 corresponds to that of FIG. 1 .
  • the compression spring 21 is tensioned between the support plate 25 and the sliding piston 17 , and extends into an axial hole 31 in the sliding piston 17 from its end facing away from the fluid space 9 .
  • Axial hole 31 is concentric to the lengthwise axis 19 , and discharges into transverse holes 33 in the sliding piston 17 .
  • These transverse holes extend radially in the vicinity of the top 23 of the sliding piston 17 , and at a right angle to one another so that they intersect on the lengthwise axis 19 .
  • transverse holes 33 in the sliding piston 17 form fluid channels which interact with the valve control edge and which form the fluid access to the fluid space 9 , by way of the axial hole 31 of the sliding piston 17 and the through holes 35 in the support plate 25 when the sliding piston is in the open position shown in FIGS. 1 and 3 .
  • FIG. 2 shows the orifices of the transverse hole 33 in the position of the sliding piston 17 shown in FIG. 2 .
  • the control edge is formed on the sleeve upper end edge 37 , see FIG. 2 .
  • the piston bore 15 in its end section forms a tapered bore section with an annular shoulder surface 39 .
  • Shoulder surface 39 interacts with an opposing shoulder surface 41 on the sliding piston 17 (see FIG. 2 ) forming a stop limiting the displacement of the sliding piston 17 in the direction to the fluid space 9 .
  • FIG. 1 shows the corresponding position of the sliding piston 17 fixed by this stop.
  • the support plate 25 formed as an abutment for the compression spring 21 , is provided with an outside thread and is screwed into an inside thread 13 formed in the connecting sleeve 11 .
  • the connecting sleeve 11 in the section adjacent to the end edge 37 has an outside thread 43 which is screwed to the corresponding inside thread of the wall of the pressure tank 1 .
  • the wall thickness of the pressure tank 1 is made greater in the threaded area for this purpose.
  • the embodiment shown on the right side in FIG. 3 has a connecting sleeve 11 which is molded on the pressure tank 1 in one piece by hot or cold forming. Otherwise, the right side embodiment does not differ from the embodiment shown on the left side in the same figure.
  • the invention is described above using embodiments in the form of bladder accumulators.
  • the invention can be equally used advantageously in hydraulic accumulators of a different design, for example in membrane accumulators or piston accumulators.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Supply Devices, Intensifiers, Converters, And Telemotors (AREA)
US10/399,445 2000-10-18 2001-10-12 Hydroaccumulator, in a particular a bladder accumulator Expired - Lifetime US6988514B2 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10051580A DE10051580A1 (de) 2000-10-18 2000-10-18 Hydrospeicher, insbesondere Blasenspeicher
DE10051580.0 2000-10-18
PCT/EP2001/011838 WO2002033266A2 (de) 2000-10-18 2001-10-12 Hydrospeicher, insbesondere blasenspeicher

Publications (2)

Publication Number Publication Date
US20040020543A1 US20040020543A1 (en) 2004-02-05
US6988514B2 true US6988514B2 (en) 2006-01-24

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ID=7660181

Family Applications (1)

Application Number Title Priority Date Filing Date
US10/399,445 Expired - Lifetime US6988514B2 (en) 2000-10-18 2001-10-12 Hydroaccumulator, in a particular a bladder accumulator

Country Status (5)

Country Link
US (1) US6988514B2 (ja)
EP (1) EP1327081B1 (ja)
JP (1) JP4170754B2 (ja)
DE (2) DE10051580A1 (ja)
WO (1) WO2002033266A2 (ja)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20040217559A1 (en) * 2003-02-10 2004-11-04 Michael Schlitzkus Device for damping pressure pulsations
US20060225800A1 (en) * 2003-10-31 2006-10-12 Norbert Weber Device for damping pressure surges
US20170088109A1 (en) * 2014-05-21 2017-03-30 Robert Bosch Gmbh Damping Device

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10247688A1 (de) * 2002-04-26 2003-11-06 Continental Teves Ag & Co Ohg Hochdruckspeicher
US20080189925A1 (en) * 2005-08-23 2008-08-14 Taho Valves Corporation Method for making water buffer device
US20160033051A1 (en) * 2014-07-31 2016-02-04 Parker-Hannifin Corporation Shutoff valve assembly
CA3166177A1 (en) * 2019-12-27 2021-07-01 Performance Pulsation Control, Inc. Bladder saver device

Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2331921A (en) * 1938-05-31 1943-10-19 Mercier Jean Storage device
US2345124A (en) * 1941-12-01 1944-03-28 New York Air Brake Co Accumulator
USRE23333E (en) * 1951-01-23 Storage device
USRE23437E (en) 1951-12-04 Oleopneumatic device
US2731038A (en) * 1953-01-26 1956-01-17 Purcell Howard Milne Hydraulic accumulator
US3038501A (en) * 1957-12-05 1962-06-12 Greer Hydraulies Inc Pressure vessel
FR79885E (fr) 1961-05-31 1963-02-08 Perfectionnements aux séparateurs de fluide sous pression
DE2452882A1 (de) 1974-11-07 1976-05-13 Sugimura Zylindrischer sammler
US4068684A (en) 1975-08-11 1978-01-17 Greer Edward M Locking ring assembly for the liquid port of a pressure accumulator
US4112978A (en) * 1976-08-04 1978-09-12 Robert Bosch Gmbh Valve for an opening of a pressure vessel
US4136714A (en) * 1976-12-27 1979-01-30 Creavco, Inc. Accumulator drain closure
US4509557A (en) 1983-07-08 1985-04-09 Nobuyuki Sugimura Accumulator
US5368073A (en) * 1993-10-07 1994-11-29 Essef Corporation Hydropneumatic pressure vessel having an improved diaphragm assembly
WO2000031420A1 (de) 1998-11-25 2000-06-02 Continental Teves Ag & Co. Ohg Druckmittelspeicher
US6460571B1 (en) * 2001-03-13 2002-10-08 Parker-Hannifin Corporation Crimped piston/membrane accumulator

Patent Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
USRE23333E (en) * 1951-01-23 Storage device
USRE23437E (en) 1951-12-04 Oleopneumatic device
US2331921A (en) * 1938-05-31 1943-10-19 Mercier Jean Storage device
US2345124A (en) * 1941-12-01 1944-03-28 New York Air Brake Co Accumulator
US2731038A (en) * 1953-01-26 1956-01-17 Purcell Howard Milne Hydraulic accumulator
US3038501A (en) * 1957-12-05 1962-06-12 Greer Hydraulies Inc Pressure vessel
FR79885E (fr) 1961-05-31 1963-02-08 Perfectionnements aux séparateurs de fluide sous pression
DE2452882A1 (de) 1974-11-07 1976-05-13 Sugimura Zylindrischer sammler
US4068684A (en) 1975-08-11 1978-01-17 Greer Edward M Locking ring assembly for the liquid port of a pressure accumulator
US4112978A (en) * 1976-08-04 1978-09-12 Robert Bosch Gmbh Valve for an opening of a pressure vessel
US4136714A (en) * 1976-12-27 1979-01-30 Creavco, Inc. Accumulator drain closure
US4509557A (en) 1983-07-08 1985-04-09 Nobuyuki Sugimura Accumulator
US5368073A (en) * 1993-10-07 1994-11-29 Essef Corporation Hydropneumatic pressure vessel having an improved diaphragm assembly
WO2000031420A1 (de) 1998-11-25 2000-06-02 Continental Teves Ag & Co. Ohg Druckmittelspeicher
US6478051B1 (en) * 1998-11-25 2002-11-12 Continental Teves Ag & Co., Ohg Pressure means storage device
US6460571B1 (en) * 2001-03-13 2002-10-08 Parker-Hannifin Corporation Crimped piston/membrane accumulator

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20040217559A1 (en) * 2003-02-10 2004-11-04 Michael Schlitzkus Device for damping pressure pulsations
US7240696B2 (en) * 2003-02-10 2007-07-10 Robert Bosch Gmbh Device for damping pressure pulsations
US20060225800A1 (en) * 2003-10-31 2006-10-12 Norbert Weber Device for damping pressure surges
US7308910B2 (en) * 2003-10-31 2007-12-18 Hydac Technology Gmbh Device for damping pressure surges
US20170088109A1 (en) * 2014-05-21 2017-03-30 Robert Bosch Gmbh Damping Device
US10227065B2 (en) * 2014-05-21 2019-03-12 Robert Bosch Gmbh Damping device

Also Published As

Publication number Publication date
DE10051580A1 (de) 2002-05-08
JP2004514094A (ja) 2004-05-13
EP1327081A2 (de) 2003-07-16
JP4170754B2 (ja) 2008-10-22
WO2002033266A3 (de) 2002-08-29
DE50106341D1 (de) 2005-06-30
WO2002033266A2 (de) 2002-04-25
US20040020543A1 (en) 2004-02-05
EP1327081B1 (de) 2005-05-25

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